Auger drill



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ATTORNEYS E. M. SPRY April 18, 1950 Patented Apr. 18, 1950 UNITED STATESPATENT OFFICE AUGER DRILL Earl M. Spry, Plymouth, Pa.

Application December 30, 1947, Serial No. 794,517

Claims. 1

The present invention relates to boring tools and more particularly toan improved drill or auger stem or body for use in drilling coal, rock.shale, gypsum, iron ore, and like material.

In drill stems or bodies of the type to which this invention relates thetransverse section thereof is of vital importance since its shape is thematerial factor in obtaining eflicient results, and such stems, asheretofore constructed, are lacking in such section shape as will pullthe cuttings out with a minimum of accompanying dust; are formed withimproper flight angles; have rough or sharp edges susceptible ofinjuring the hands of the operator; and have been designed with littleregard to whip incident to drilling operations.

Some of the objects of the present invention are: to provide an improveddrill stem or body formed as quarter octagon steel with a new and noveltransverse section; to provide a drill stem materially stronger than anyheretofore in use and wherein equal distribution of material isobtained; to provide a drill stem having a section which gives maximumresistance to whip in use so that crystallization of the steel iseliminated and breakage reduced to a minimum; to provide a drill stemwherein there is a minimum flight drag due to the smooth surfaces of theflights; to provide a drill stem wherein a novel transverse sectionensures the cuttings being pulled out with practically all dust beingeliminated; and to provide other improvements as will hereinafterappear.

in the accompanying drawings, Fig. 1 represents a side elevation of adrill stem embodying the present invention, the same being shown priorto twisting; Fig. 2 represents the same in finished form after twisting;and Fig. 3 represents a section on an enlarged scale taken on line 3--3of Fig. 1, as illustrative of the section throughout the length of thestem, but indicating in dotted lines the bore of a hole to illustratethe relation of the stem section thereto.

Referring to the drawings, Fig. 1 illustrates a bar It] ofdrill steelpreliminarily shaped from square bar stock by the usual rollingoperation to pass the bar through a preshaped die to transform thesquare section into the modified quarter octagon section of the presentinvention. In this drill section two opposite corners of the formersquare section provide two smooth, plane surface edges l l and I! asouter faces respectively of two diametrically opposite, relative narrowribs l3 and M of like length extending longitudinally throughout thelength of the bar ID. The base of the rib l3 curves outwardly to mergesmoothly into the former sides I5 and [B of the square section stock,which diverge to intersect respectively two smooth, plane surfaces l1and I8 of two parallel lines of slightly rounded intersections 20 and2|. Likewise, the base of the rib M curves outwardly to merge smoothlyinto the former sides 22 and 23 of the square section stock, whichdiverge to intersect respectively theaforesaid surfaces l7 and I8 in twoparallel lines: of slightly rounded intersections 24 and 25. The: twolines of intersections 20 and 2| lie in the: same transverse plane,while the two lines of intersections 24 and 25 lie in a differenttrans-- verse plane, the two planes being parallel and; spaced by thewidth of the respective surfaces: l1 and I8. Thus, these surfaces 11 andI8 area the result of displacing the former two opposite: corners of thesquare section stock by truncated; portions respectively, while the ribsl3 and Hi are elongated extensions of the other two cor ners of theformer square section stock. result of this transition from a squaresection. stock to a modified quarter octagon section, a. relativelyheavy body core is obtained with the two surfaces I! and I8 spaced aparta shorter distance than the edges H and I2 upon the diametricallyextended ribs l3 and I4. This is an important distinction over priordrill stem sections in that a substantially massive body or core portionis provided capable of effectively resisting whip and distortion whenthe stem is in use: in the complete drill assembly.

With the novel section of the invention formed,

in the bar as above described, and as shown in, Fig. 1, the body of thedrill blank is then twisted; about its longitudinal axis in a well-knownman-.

ner, either heated or cold, according to the character of the steel fromwhich the stem is rolled; When properly twisted, the ribs I l and I2form v equally spaced spiral flights throughout the-e length of thestem, while maintaining the re quired novel section at all transversepoints throughout the length of the stern. In consequence a stem isprovided in which the rib edges H and I2 are equally spaced radiallyfrom the center of the core body and give a diameter arranged to fit theinternal diameter of the hole being bored, while the smooth surfaces l1and I8 are each well spaced from the wall of the hole to thereby provideappreciable equal spiral clearances which serve to convey displacedmaterial from the hole entering end of the stem to the other end. Due tothe smooth and rounded intersections and edges crushing of the materialinto dust form is practically eliminated. The efficiency of thisnon-crushing feature is largelyhammers. or jaokhammers, one' nfdofthe:afore= said stem is formed with an integral extension 26 which isexternally threaded to mount a jack bit as the drill for working end ofthe stem. The

threaded construction shown is preferred-be cause present day removablebits are threaded but other bit-securing means can besemployed sincethis forms no part of the presentinvention The opposite end of the stemis formed with an elongated shank 2'! of such lengths as will-allow.proper connection to the jackhammer and in section may be of hexagonsection or suchother section as will allow'attachment of theaforesaidjackhammer. Also, at a convenient distance from-the end of the shank .acircumferential integral collar 28 is provided to receive the thrust ofthe hammer in use.

It will now be apparent that a drill steel stem, of novel quarteroctagon section has been devised differing from a conventional quarteroctagon steel in that two opposite sides are reduced inspaceddiameterand so Working the material that displaced material is added totheother two. opposite sides in theform .of outwardly projecting ribs.By twistingthis novel section of quarter octagon steel, a steel sternvis formed far stronger,- than various types of twisted drills now inuse, in that the novel section shape furnishes ,eogual distribution ormaterial inthe ribs of the stem.

Also, this section reduces whip to a minimum and thus eliminatescrystallization of the steel whereby less breakage occurs.

have caused cutting of the hands in use.

clearances provided furnishes, a minimum flight drag due to thesmoothness of the flight for pulling outv cuttings. health of thedriller in that it is a dustless drill.

It will be understood also that the stemismade in various lengths forstartinga hole Withshort detachable jackbits- Having thus described. myinvention, I claim:

1. auger drill'formed from modified quarter-- octagon drill stem,comprising a solid steel body.

formed by two truncatedssides. arranged :with

juxtaposed spaced apart bases and outer surfaces.

parallel to each other and two ribsforrned respec-.

tively as oppositely disposed radial extensionsof.

said bases terminating in cutting edges, said sides and ribs extendinghelically substantially; throughout the length of said stem inalternateradial. relation, the distance between said edges.

being greater than the distance between said sur- This novel stemhas nosharp or rough edges which heretofore. Furthermore, the elongated'twistwith the smooth This action also protect the;

'50 lengths and longer lengths as, th .hole becomes deeper and can beused with all typesand sizes of faces whereby a massive torsionresisting core is provided having a plurality of smooth helical channelsbetween said ribs for displaced material and means respectively at theends of said body for attaching drill bits and power hammers.

2. An auger drill formed from modified quarter octagon twisted drillstem comprising a steel body, means at one end for attaching a drillbit, means at the other end to cooperate with a power hammer, aid :bodyhavingka transverse section formed by'two' diametrically opposite ribsradially dimensioned to fit the internal diameter of the hole to bebored, and two oppositely disposed smooth surfaces respectively formedby a pair of body sides converging outwardly from said ribs a radialdistance less than the spacing of the ends otsaid ribs, whcreby amassive torsion resisting core is provided having clearances betweensaid surfaces and the wall of said hole during a boring operation.

3. A section of a modified quarter octagonsteel twisted. drill body,twooppositely disposed truncated sides in-v 1 tegral with said body, andtwo ribs integral with said body and projecting oppositely between saidtruncated sides, the dimension of the spacing between the edges of saidribs being greater. than the spacing between the surfaces respectively-formed by. the convergence of said truncated,

sides.

4. A- drill rod comprising a bodyof substantially square cross section,two oppositely disposed corners of the body section being truncated toprovide a pair ofrelatively narrow faces, the I remaining corners beingprovided with extending I ribs, the distancebetween the extremities ofthe ribs being greater than the distance between the truncated corners,said body with the ribs being twisted in helical formation whereby amassive torsion-resisting core is formed with helical ribs andclearances.

5.- A drill rod blank comprising a twisted-body of substantially squarecross section, two oppositely disposed corners of the body section beingtruncated, and the other two oppositely disposed cornersbeing providedwith extending ribs, the

distance between the extremities of the ribs being greater than thedistance between the truncated corners.

EARL M. 'SPRY;

REFERENCES CITED The., following references are of record in the ifile,of patent:

UNITED STATES PATENTS- Number Name Date 1,216,628 Teasck Feb. 20, 19172,320,612 Kandle June 1, 1943 FOREIGN PATENTS Number Country Date130,735 Switzerland Mar. 1, 1929 260,878 Great Britain Nov. '11, 1926 astem of such uniform sectionv throughout its operative length comprisinga;

